Dr. Anthony Haynes

Biographical Sketch

Dr. Haynes obtained his BSc from the University of Exeter in 1986. After obtaining his PhD from the University of Nottingham in 1989, he became a BP Chemicals Research Fellow at the University of Sheffield until 1993, when he was appointed the BP Chemicals Lecturer in Homogeneous Catalysis. In 1998 he was appointed as Lecturer at the University of Sheffield. From this post he was promoted to Senior Lecturer (2002) and Reader (2009).

Research Keywords

Homogeneous Catalysis, Organometallic Chemistry, Carbonylation, Reaction Mechanisms, Kinetics, Isotopic Labelling, High Pressure Infrared Spectroscopy, Ligand effects.

Teaching Keywords

Transition Metal Chemistry; Homogeneous Catalysis

Selected Publications:

Ligand Effects on the Reactivity of Cobalt Acyl Complexes, J. M. Birbeck, A. Haynes, H. Adams, L. Damoense and S. Otto, ACS Catalysis, 2012, 2, 2512-2523.
Dicarbonylrhodium(I) Complexes of Bipyridine Ligands with Proximate H-Bonding Substituents and Their Application in Methyl Acetate Carbonylation, Christopher M. Conifer, David J. Law, Glenn J. Sunley, Anthony Haynes, John R. Wells, Andrew J. P. White and George J. P. Britovsek, Eur. J. Inorg. Chem. 2011, 3511-3522.
Mechanistic Study of Rhodium/xantphos-Catalyzed Methanol Carbonylation, Gary L. Williams, Christopher M. Parks, C. Robert Smith, Harry Adams, Anthony Haynes, Anthony J. H. M. Meijer, Glenn J. Sunley and Sander Gaemers, Organometallics 2011, 30, 6166-6179.
Catalytic Methanol Carbonylation. A. Haynes In Advances in Catalysis; Elsevier Academic Press Inc: San Diego, 2010; Vol. 53.
Identification of the Reactive cis,mer Isomer of [Ir(CO)(2)I3Me](-): Relation to the Mechanism of Iridium-Catalyzed Methanol Carbonylation, A. Haynes, A. J. H. M. Meijer, J. R. Lyons and H. Adams, Inorg. Chem. 2009, 48, 28-35.
Reactivity of Rhodium(I) Iminophosphine Carbonyl Complexes with Methyl Iodide, J. Best, J. M. Wilson, H. Adams, L. Gonsalvi, M. Peruzzini and A. Haynes, Organometallics 2007, 26, 1960-1965.
Ligand Stereoelectronic Effects in Complexes of Phospholanes, Phosphinanes, and Phosphepanes and Their Implications for Hydroformylation Catalysis, R. Angharad Baber, Mairi F. Haddow, Ann J. Middleton, A. Guy Orpen, Paul G. Pringle, Anthony Haynes, Gary L. Williams and Rainer Papp, Organometallics 2007, 26, 713-725.
The synthesis, characterisation and reactivity of 2-phosphanylethylcyclopentadienyl complexes of cobalt, rhodium and iridium, Ann C. McConnell, Peter J. Pogorzelec, Alexandra M. Z. Slawin, Gary L. Williams, Paul I. P. Elliott, Anthony Haynes, Andrew C. Marr and David J. Cole-Hamilton, Dalton Transactions 2006, 91-107.
Formation and Reactivity of Ir(III) Hydroxycarbonyl Complexes, Paul I. P. Elliott, Claire E. Haslam, Sharon E. Spey and Anthony Haynes, Inorganic Chemistry 2006, 45, 6269-6275.
Promotion of Iridium-Catalyzed Methanol Carbonylation: Mechanistic Studies of the Cativa Process, Anthony Haynes, Peter M. Maitlis, George E. Morris, Glenn J. Sunley, Harry Adams, Peter W. Badger, Craig M. Bowers, David B. Cook, Paul I. P. Elliott, Talit Ghaffar, Helena Green, Tim R. Griffin, Marc Payne, Jean M. Pearson, Michael J. Taylor, Paul W. Vickers and Rob J. Watt, J. Am. Chem. Soc. 2004, 126, 2847-2861.
Facile Alkene Insertion into a Rhodium(III)-Acetyl Bond: Potential Catalysts for CO/Alkene Copolymerization, Anthony Haynes, Claire E. Haslam, Kevin J. Bonnington, Louise Parish, Harry Adams, Sharon E. Spey, Todd B. Marder and David N. Coventry, Organometallics 2004, 23, 5907-5909.
Oxidative Addition of MeI to a Rhodium(I) N-Heterocyclic Carbene Complex. A Kinetic Study, Helen C. Martin, Neil H. James, John Aitken, Joseph A. Gaunt, Harry Adams and Anthony Haynes, Organometallics 2003, 22, 4451-4458.
Steric and Electronic Effects on the Reactivity of Rh and Ir Complexes Containing P-S, P-P, and P-O Ligands. Implications for the Effects of Chelate Ligands in Catalysis, Luca Gonsalvi, Harry Adams, Glenn J. Sunley, Evert Ditzel and Anthony Haynes, J. Am. Chem. Soc. 2002, 124, 13597-13612.

Research Interests

Rh-xant-spectra The Haynes group investigates mechanistic aspects of homogeneous transition metal catalysed reactions, particularly industrially important processes such as methanol carbonylation and alkene hydroformylation. Synthetic, spectroscopic, kinetic and computational methods are used to study the structure and reactivity of organometallic complexes and their roles in catalysis.

Mechanisms of rhodium and iridium catalysed methanol carbonylation
The catalytic carbonylation of methanol to acetic acid is one of the most significant industrial applications of homogeneous transition metal catalysis. We have a long-standing research collaboration with BP Chemicals, who operate methanol carbonylation plants worldwide, and introduced a new process(Cativa ^TM) in 1995 that uses a promoted iridium/iodide catalyst. Highlights of our mechanistic studies include the first spectroscopic detection of a highly reactive Rh-methyl intermediate in the rhodium-catalysed process[1] and elucidation of the role of promoters in the iridium-based system.[2] We recently showed that the rate of migratory CO insertion in [Ir(CO)₂I₃Me]^- is dramatically increased by isomerisation to place a CO ligand trans to methyl.[3]

Ligand effects on oxidative addition and migratory CO insertion
We are interested in how the rates of key steps in catalytic cycles can be influenced by the electronic and steric properties of "spectator" ligands, e.g. phosphines, imines and N-heterocyclic carbenes. Strongly donating ligands tend to promote oxidative addition and retard migratory CO insertion, whereas sterically bulky ligands tend to have the opposite effects on these steps.[4] In a recent study of the mechanism of rhodium/xantphos-catalysed methanol carbonylation it was found that the key intermediates contained xantphos coordinated as a tridentate "pincer" ligand and the nucleophilicity of the metal centre is enhanced by a Rh---O interaction.[5]

Computational studies
Our experimental studies are complimented by theoretical calculations, carried out in collaboration with Dr. Anthony Meijer in this department. We are interested in modelling trends in organometallic reactivity and spectroscopic properties, e.g. vibrational spectra of metal carbonyl complexes.

Facilities
The department is well-equipped with modern instrumentation for NMR spectroscopy, X-ray crystallography, mass-spectrometry and chromatography. In addition, the group has dedicated FTIR instruments for kinetic measurements, including high pressure and stopped-flow IR cells.

References
1. (a) JACS, 1991, 113, 8567; (b) JACS, 1993, 115, 4093.
2. JACS, 2004, 126, 2847.
3. Inorg. Chem., 2009, 48, 28
4. (a) JACS, 2002, 124, 13597; (b) Organometallics, 2003, 22, 1047; (c) Organometallics, 2003, 22, 4451.
5. Organometallics, 2011, 30, 6166.

Inorganic Chemistry

Undergraduate Courses Taught

Hydrogen and the s- and p-block elements (Year 1)
This segment introduces key concepts regarding the structures and properties of the s- and p-block elements.
Reactivity and mechanisms of d-block complexes (Year 2)
This course describes and explains the reaction mechanisms of transition metal complexes.
Organometallic Chemistry 1: longitudinal ligands (Year 3)
This segment deals with the synthesis, structure, bonding and reactivity of transition metal complexes containing metal-carbon σ-bonds. It introduces the role of these complexes in catalytic reactions.
Homogeneous Catalysis (Year 4)
This course describes the chemical basis behind some economically important industrial processes which use homogeneous transition metal catalysts to manufacture important products such as solvents, pharmaceuticals, polymers and detergents.

Tutorial & Workshop Support

First Year General Tutorials.
Second Year Inorganic Chemistry Tutorials.
Third Year Workshops.
Fourth Year Workshops.
Third Year Literature Review.

Laboratory Teaching

Second Year Lab demonstrating.
Third Year Labd demonstrating.
Fourth Year Research Project.